           (fn [[l ls]]
             (if (empty? ls)
               nil
-              (stats/mean (pmap #(/ (t/in-seconds (t/interval (:ts l) (:ts %))) 3600) ls)))))
+              (stats/mean (pmap #(/ (t/in-seconds (t/interval (:ts l) (:ts %))) 60) ls)))))
          (remove nil?)
          statistics)
     :distribution

          (fn [[l ls]]
            (if (empty? ls)
              nil
              (statistics (pmap #(/ (t/in-seconds (t/interval (:ts l) (:ts %))) 3600) ls)))))
         (remove nil?))
    :evolution
    (->> (t/interval t0 tmax)

                  (fn [[l ls]]
                    (if (empty? ls)
                      nil
                      (stats/mean (pmap #(/ (t/in-seconds (t/interval (:ts l) (:ts %))) 60) ls)))))
                 (remove nil?)
                 statistics))))
    :unrelated))
